This will need to be checked from your Google Console. May i connect with you remotely to do it for you? Thanks
I sent you request for remote service; please accept it then follow steps here to connect with me.
They don't assist with such issues, but i can guide here what needs to be done. You will need to login to your google console, if it doesn't exist, then sign up for it. Locate and see which URL from your site is infected, then have your site checked for viruses, malwares and remove it. (this will need to be done by a developer)